The fact that Amiga "lost" to the PC was in my opinion not the "Amiga is a toy!". It was just as much caused by Commodore itself. The Amiga was extraordinarily mis-managed by CBM (just look what happened when they were designing the A600 to be a cheaper alternative to A500, and ended up putting so much stuff in that it launched at a *higher* price point). It was poorly marketed as well.

As for Windows not being released until 1990, that's plain wrong. Windows 3.0 was released in 1990 and was a huge success compared to earlier version. Windows 1.0 launched in 1985. But you're right if you meant to say "usable version" of Windows :-)

I think the real reason the PC won was Compaq and their reverse engineering of the BIOS, laying the groundwork for an open standard. Computing is full of examples that, given enough time, open standards win.